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A compound is found to be 62.1% C, 5.21% H, 12.1% N, and the remainder O by mass.  If the molar mass of the compound is 697 g/mol, what is the molecular formula of the compound? When putting the formula in, carbon must be first, then H, N, and O.  Do not try to put in subscripts, just put the numbers in-line.  Example:  C12H34N56O78 _______

There are ________ ng in a pg.

When balancing the equation below, the coefficient of K3PO4 would be: P4O10  +  KOH  →  K3PO4  +  H2O _______

The formula weight of Zn(ClO4)2 is ________ amu.

Given the Chart below, fill in all of the blanks that contain a BOLD RED number.  For charges, put in the number first then the sign of the charge (+ or -). Symbol Number of Protons Number of Neutrons Number of Electrons Net Charge Mass B 5 6 5 1 11 Fe 2 28 24 3 4 As 5 6 7 3+ 76 8 9 16 18 10 31

The mineral leadhillite, which is essentially Pb4(SO4)(CO3)2(OH)2, contains what percentage of oxygen by mass?

Which of the following are combustion reactions? 1)  CH4(g)  +  O2(g)  →  CO2(g)  +  H2O(l) 2)  CaO(s)  +  CO2(g)  →  CaCO3(s) 3)  PbCO3(s)  →  PbO(s)  +  CO2(g) 4)  CH3OH(l)  +  O2(g)  →  CO2(g)  +  H2O(l)

The SI (International System of Units) unit for mass is ________.

A 10.00 g sample of solid sodium bicarbonate (the active ingredient in baking soda) completely decomposes into solid sodium hydroxide and carbon dioxide gas when heated.  After the sodium hydroxide cools, it has a mass of 4.76 g.  What mass of carbon dioxide must have been formed?

3.337 g/cm3 = ________ kg/m3